A composite expandable device with polymeric covering and bioactive coating thereon, delivery apparatus and method are disclosed in U.S. Pat. No. 6,371,980, issued Apr. 16, 2002. In connection with the expandable stent and the polymeric covering forming a graft carried thereby it has been found that it may be possible for the graft to move or become dislodged from its most desirable position on the stent. There is therefore a need for a new and improved stent graft assembly and method which overcomes this possible difficulty.